This invention relates to rotary lobe pumps. Rotary lobe pumps are used in industry for positive-displacement pumping of foodstuffs, pharmaceuticals, and other similar materials. When handling these materials, it is important that cross-contamination and chemical interaction with other materials are avoided.
Known rotary lobe pumps include provision for dismantling by the user. In this way, components of the pump that come into contact with the pumped material can be cleaned and sterilized between different batches. A problem associated with this cleaning and sterilization process is that it is time consuming and prone to errors. Any errors in the cleaning process may result in contamination of the pumped material and/or loss of production.
In general, components of rotary lobe pumps are manufactured with high dimensional accuracy and low tolerances. It is particularly important that the form of the lobed rotors and the walls of the pumping chamber are accurately controlled, so as to achieve the desirable characteristics of low noise and wear and high efficiency. In known pumps, the required accuracy is achieved by machining components from metal, for example stainless steel.